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A Study of Teacher Feedback in Different English Class Types
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作者 陈欢 《海外英语》 2016年第13期229-231,共3页
This essay mainly focuses on the feedback move in IRF(initiate- response- feedback) to investigate the characters and functions of teacher feedback in different class types through classroom observation. The research ... This essay mainly focuses on the feedback move in IRF(initiate- response- feedback) to investigate the characters and functions of teacher feedback in different class types through classroom observation. The research finds that(1) teachers in different class types prefer to adopt evaluative feedback and use more positive feedback.(2) the proportion of each feedback is different in listening and speaking, reading and writing class. The implications are that English teachers in senior high school should adopt different feedback flexibly and consider what kind of feedback is more likely elicit the students' output in different class types. 展开更多
关键词 TEACHER classroom LISTENING SPEAKING LIKELY writing Feedback adopt LESSON SENIOR
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PERFORMANCE ANALYSIS OF POWER SAVING CLASS OF TYPE Ⅲ IN IEEE 802.16E WITH USER INITIATED TRAFFIC
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作者 Gao Jie Jin Shunfu Tian Naishuo Han Li 《Journal of Electronics(China)》 2010年第1期127-133,共7页
A novel method for analysing the performance of power saving class of Type III in IEEE 802.16e is proposed, which is applicable to design, maintenance and management for mobile wireless metropolitan area network. Cons... A novel method for analysing the performance of power saving class of Type III in IEEE 802.16e is proposed, which is applicable to design, maintenance and management for mobile wireless metropolitan area network. Considering the memoryless nature of user initiated packet arrival, a Geom/G/1 queue model with multiple vacations and setup period is built to capture the principle for the power saving class of Type III. By using an embedded Markov chain method and the boundary state variable theory, we obtain the queueing measures such as queueing length, waiting time and busy cycle in steady state. Correspondingly, we derive explicitly the performance measures for the power saving class of Type III in terms of handover ratio, energy saving ratio, and average packet response time. Based on numerical results, we develop a cost function to determine numerically the optimal length of sleep window and the minimal cost with different offered loads. 展开更多
关键词 system IEEE 802.16e Power saving class of type III Sleep mode Multiple vacations QUEUEING
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Hyperglycemia promotes overexpression of SR-BII isoform of the scavenger receptor class B type I in type 2 diabetes mellitus: A study in Juana Koslay City, San Luis, Argentina
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作者 Gisela V. Mendoza Susana Siewert +3 位作者 Irma González María C. Della Vedova Gustavo Fernandez Marta S. Ojeda 《Journal of Diabetes Mellitus》 2013年第4期172-183,共12页
The scavenger receptor class B type I (SR-BI) is a high-density lipoprotein (HDL) receptor involved in reverse cholesterol transport. Some studies reported the association to be stronger in the presence of diabetes. T... The scavenger receptor class B type I (SR-BI) is a high-density lipoprotein (HDL) receptor involved in reverse cholesterol transport. Some studies reported the association to be stronger in the presence of diabetes. The full length gene encoding SR-BI is comprised in 13 exons that are alternatively spliced to produce two major transcripts: the full length SR-BI and the splice variant SR-BII, in which exon 12 is skipped. Considering that type 2 diabetes status is characterized by changes in the concentration of plasma lipids, modifications in lipoprotein size and composition, which may be important modulators of the SR-BI expression;the aims of the study were to examine the influence of SR-BI polymorphism (rs838895) on lipid profile and SR-BI mRNA expression in a population of diabetic patients living in Juana Koslay City. Blood samples were drawn from controls (n = 40) and Type 2 diabetic patients (n = 66) and DNA and total RNA were obtained. SR-BI mRNA expression was measured by RT-PCR and SR-BI polymorphism was detected by Tetra Primer ARMSPCR. Compared to controls, diabetic patients had higher fasting serum glucose, glycated hemoglobin, triglycerides, total cholesterol, lowdensity lipoprotein cholesterol, and lower highdensity lipoprotein cholesterol. SR-BI mRNA expression was lower in T2DM when compared to controls, suggesting that the hyperglycemia presents in T2DM patients down-regulates SR-BI mRNA expression. Interestingly, we found that decreased SR-BI expression resulted in markedly increased plasma LDL concentrations in T2DM subjects, and the overexpression of SRBII isoform is responsible for the markedly increased plasma LDL-c concentrations. The polymorphism (rs838895) did not modify the mRNA level of SR-BI in leucocytes from control and diabetic patients. This study provides novel evidence suggesting that hyperglycemia may affect reverse cholesterol transport by controlling SRBI expression in diabetic patients. LDL cholesterol levels are associated with low SR-BI mRNA expression in T2DM. 展开更多
关键词 type 2 Diabetes Mellitus HYPERGLYCEMIA SCAVENGER Receptor class B type I and Polymorphism
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Classification and Net Primary Productivity of the Southern China's Grasslands Ecosystem Based on Improved Comprehensive and Sequential Classification System(CSCS) Approach 被引量:7
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作者 SUN Zheng-guo SUN Cheng-ming +2 位作者 ZHOU Wei JU Wei-min LI Jian-long 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2014年第4期893-903,共11页
This research classified vegetation types and evaluated net primary productivity (NPP) of southern China's grasslands based on the improved comprehensive and sequential classification system (CSCS), and proposed ... This research classified vegetation types and evaluated net primary productivity (NPP) of southern China's grasslands based on the improved comprehensive and sequential classification system (CSCS), and proposed 5 thermal grades and 6 humidity grades. Four classes of grasslands vegetation were recognized by improved CSCS, namely, tundra grassland class, typical grassland class, mixed grassland class and alpine grassland class. At the type level, 14 types of vegetations (9 grasslands and 5 forests) were classified. The NPP had a trend to decrease from east to west and south to north, and the annual mean NPP was estimated to be 656.3 g C m-2 yr-1. The NPP value of alpine grassland class was relatively high, generally more than 1200 g C m2 yr-1. The NPP value of mixed grassland class was in a range from 1 000 to 1200 g C m-2 yr-1. Tundra grassland class was located in southeastern Tibet with high elevation, and its NPP value was the lowest (〈600 g C m'2yrl). The typical grassland class distributed in most of the area, and its NPP value was generally from 600 to 1000 g C m-2 yr-1. The total NPP value in the study area was 68.46 Tg C. The NPP value of typical grassland class was the highest (48.44 Tg C), and mixed grassland class was the second (16.54 Tg C), followed by alpine grassland class (3.22 Tg C), with tundra grassland class being the lowest (0.25 Tg C). For all the grasslands types, the total NPP of forest meadow was the highest (34.81 Tg C), followed by sparse forest brush (16.54 Tg C), and montane meadow was the lowest (0.01 Tg C). 展开更多
关键词 improved CSCS hydro-thermal pattern southem China grasslands classes and types net primary productivity (NPP)
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L^p estimates for Riesz transform and their commutators associated with Schr?dinger type operator 被引量:1
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作者 CHEN Xiao-li CHEN Jie-cheng 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2016年第1期112-126,共15页
. Let H2 = (-△)2 + V2 be the Schr6dinger type operator, where V satisfies reverse HSlder inequality. In this paper, we establish the Lp boundedness for V2 H2- 1, H21 V2, VH2- 1/2 and Hfl/2V, and that of their comm... . Let H2 = (-△)2 + V2 be the Schr6dinger type operator, where V satisfies reverse HSlder inequality. In this paper, we establish the Lp boundedness for V2 H2- 1, H21 V2, VH2- 1/2 and Hfl/2V, and that of their commutators. We also prove that H^IV2, Hfl/2V are bounded from BMOL to BMOL. 展开更多
关键词 Schrodinger type operator Bq class BMOL commutator.
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Solving the Class Equation x<sup>d</sup>= β in an Alternating Group for Each β ∈ C<sup>α</sup>∩ H<sub>n</sub><sup>c</sup>and n >1
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作者 Shuker Mahmood Andrew Rajah 《Advances in Linear Algebra & Matrix Theory》 2012年第2期13-19,共7页
The main purpose of this paper is to solve the class equation in an alternating group, (i.e. find the solutions set ) and find the number of these solutions where ranges over the conjugacy class in and d is a positive... The main purpose of this paper is to solve the class equation in an alternating group, (i.e. find the solutions set ) and find the number of these solutions where ranges over the conjugacy class in and d is a positive integer. In this paper we solve the class equation in where , for all . is the complement set of where { of , with all parts of are different and odd}. is conjugacy class of and form class depends on the cycle type of its elements If and , then splits into the two classes of . 展开更多
关键词 Alternating Groups PERMUTATIONS Conjugate classes Cycle type FROBENIUS Equation
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Predicting Βeta-Turns and Βeta-Turn Types Using a Novel Over-Sampling Approach
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作者 Lan Anh T. Nguyen Xuan Tho Dang +8 位作者 Tu Kien T. Le Thammakorn Saethang Vu Anh Tran Duc Luu Ngo Sergey Gavrilov Ngoc Giang Nguyen Mamoru Kubo Yoichi Yamada Kenji Satou 《Journal of Biomedical Science and Engineering》 2014年第11期927-940,共14页
β-turn is one of the most important reverse turns because of its role in protein folding. Many computational methods have been studied for predicting β-turns and β-turn types. However, due to the imbalanced dataset... β-turn is one of the most important reverse turns because of its role in protein folding. Many computational methods have been studied for predicting β-turns and β-turn types. However, due to the imbalanced dataset, the performance is still inadequate. In this study, we proposed a novel over-sampling technique FOST to deal with the class-imbalance problem. Experimental results on three standard benchmark datasets showed that our method is comparable with state-of-the-art methods. In addition, we applied our algorithm to five benchmark datasets from UCI Machine Learning Repository and achieved significant improvement in G-mean and Sensitivity. It means that our method is also effective for various imbalanced data other than β-turns and β-turn types. 展开更多
关键词 Beta-Turns BETA-TURN typeS class-Imbalance OVER-SAMPLING
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Index-<i>p</i>Abelianization Data of <i>p</i>-Class Tower Groups
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作者 Daniel C. Mayer 《Advances in Pure Mathematics》 2015年第5期286-313,共28页
Given a fixed prime number p, the multiplet of abelian type invariants of the p-class groups of all unramified cyclic degree p extensions of a number field K is called its IPAD (index-p abeliani- zation data). These i... Given a fixed prime number p, the multiplet of abelian type invariants of the p-class groups of all unramified cyclic degree p extensions of a number field K is called its IPAD (index-p abeliani- zation data). These invariants have proved to be a valuable information for determining the Galois group of the second Hilbert p-class field and the p-capitulation type of K. For p=3 and a number field K with elementary p-class group of rank two, all possible IPADs are given in the complete form of several infinite sequences. Iterated IPADs of second order are used to identify the group of the maximal unramified pro-p extension of K. 展开更多
关键词 p-class GROUPS p-Principalization types p-class Field Towers Quadratic Fields Second p-class GROUPS p-class TOWER GROUPS Coclass Graphs
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Successive Approximation of p-Class Towers
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作者 Daniel C. Mayer 《Advances in Pure Mathematics》 2017年第12期660-685,共26页
Let F be a number field and p be a prime. In the successive approximation theorem, we prove that, for each integer n ≥ 1, finitely many candidates for the Galois group of the nth stage of the p-class tower over F are... Let F be a number field and p be a prime. In the successive approximation theorem, we prove that, for each integer n ≥ 1, finitely many candidates for the Galois group of the nth stage of the p-class tower over F are determined by abelian type invariants of p-class groups C1pE of unramified extensions E/F with degree [E : F] = pn-1. Illustrated by the most extensive numerical results available currently, the transfer kernels (TE, F) of the p-class extensions TE, F : C1pF → C1pE from F to unramified cyclic degree-p extensions E/F are shown to be capable of narrowing down the number of contestants significantly. By determining the isomorphism type of the maximal subgroups S G of all 3-groups G with coclass cc(G) = 1, and establishing a general theorem on the connection between the p-class towers of a number field F and of an unramified abelian p-extension E/F, we are able to provide a theoretical proof of the realization of certain 3-groups S with maximal class by 3-tower groups of dihedral fields E with degree 6, which could not be realized up to now. 展开更多
关键词 p-class TOWERS Galois GROUPS Second p-class GROUPS Abelian type Invariants of p-class GROUPS p-Transfer Kernel types Artin Limit Pattern Quadratic FIELDS Unramified Cyclic Extensions of Degree p Dihedral FIELDS of Degree 2p Finite p-Groups MAXIMAL Nilpotency class MAXIMAL Subgroups Polycyclic Pc-Presentations Commutator Calculus Central Series
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基于临床思维培养的中药学课程教学实践 被引量:1
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作者 孙闵 樊静娜 +3 位作者 于斌 万广宋 王荣 魏超 《高教学刊》 2025年第5期116-119,共4页
中药学课程对高校培养中医学专业人才中医临床思维具有重要意义。教师需不断提升教学能力和专业素养,重新认识中药学课程地位,积极采用线上线下相融合的混合式教学模式。教材内容整合重排,融入中医经典与名家经验及医案,传承中医药认知... 中药学课程对高校培养中医学专业人才中医临床思维具有重要意义。教师需不断提升教学能力和专业素养,重新认识中药学课程地位,积极采用线上线下相融合的混合式教学模式。教材内容整合重排,融入中医经典与名家经验及医案,传承中医药认知思维及文化,补充教材内容之不足,并积极开展第二课堂,提高应用题型测试考核比例,以优化拓展教学内容,增强教学内容的临床实用性、引导性,提升学生的思想、思考、思辨能力,提高中医思维的高度、宽度及深度。 展开更多
关键词 临床思维培养 中药学 教学模式 内容整合 第二课堂 考核题型
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Understanding the Effects of Various Factors on the Public Response to Congestion Charge: A Latent Class Modeling Approach
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作者 Sugiarto Sugiarto Tomio Miwa +1 位作者 Hitomi Sato Takayuki Morikawa 《Journal of Transportation Technologies》 2015年第2期76-87,共12页
The standard ordered response model (SORM) is a common disaggregate approach with ordered outcomes in which the effects of various exogenous attributes are assumed constant across ordinal choices. In this study, an in... The standard ordered response model (SORM) is a common disaggregate approach with ordered outcomes in which the effects of various exogenous attributes are assumed constant across ordinal choices. In this study, an innovative latent class based generalized ordered response model (LC-GORM) is formulated and used to assess the effects of various factors on respondents’ choice behavior with respect to congestion charge proposal for Jakarta, Indonesia. The proposed model probabilistically assigns respondents into selfish and altruistic class memberships (latently) based on their knowledge of the proposed scheme and their specific attributes. Aiming to capture observable preference heterogeneity across ordinal choices and allow the thresholds to be varied across observations, we parameterize the thresholds as a linear function of the exogenous variables for each ordinal preference. Using stated preference data collected in Jakarta in December 2013, we incorporate the influence of a comprehensive set of explanatory variables into four categories: charges, latent variables related to respondent’s psychological motivations, mobility attributes and socio-demographic characteristics. Empirical results obviously verify the existence of preference heterogeneity across outcomes. The findings confirm that the altruistic class are more sensitive with respect to acceptance of the scheme, while the selfish class are more sensitive with respect to rejection. The key factors influencing public acceptability include the charge level and respondent variables such as car dependency, awareness of the problem of cars in society, frequency of visits to the city center and frequency of private mode usage. 展开更多
关键词 Respondent’s CHOICE Behavior LATENT types of RESPONDENTS LATENT class CONGESTION CHARGE
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Criteria for Three-Stage Towers of <i>p</i>-Class Fields
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作者 Daniel C. Mayer 《Advances in Pure Mathematics》 2017年第2期135-179,共45页
Let p be a prime and K be a number field with non-trivial p-class group ClpK. A crucial step in identifying the Galois group G∞p of the maximal unramified pro-p extension of K is to determine its two-stage approximat... Let p be a prime and K be a number field with non-trivial p-class group ClpK. A crucial step in identifying the Galois group G∞p of the maximal unramified pro-p extension of K is to determine its two-stage approximation M=G2pk, that is the second derived quotient M&simeq;G/Gn. The family τ1K of abelian type invariants of the p-class groups ClpL of all unramified cyclic extensions L/K of degree p is called the index- abelianization data (IPAD) of K. It is able to specify a finite batch of contestants for the second p-class group M of K. In this paper we introduce two different kinds of generalized IPADs for obtaining more sophisticated results. The multi-layered IPAD (τ1Kτ(2)K) includes data on unramified abelian extensions L/K of degree p2 and enables sharper bounds for the order of M in the case Clpk&simeq;(p,p,p), where current im-plementations of the p-group generation algorithm fail to produce explicit contestants for M , due to memory limitations. The iterated IPAD of second order τ(2)K contains information on non-abelian unramified extensions L/K of degree p2, or even p3, and admits the identification of the p-class tower group G for various infinite series of quadratic fields K=Q(√d) with ClpK&simeq;(p,p) possessing a p-class field tower of exact length lpK=3 as a striking novelty. 展开更多
关键词 Hilbert p-class FIELD TOWER p-class GROUP p-Principalization types Quadratic Fields Unramified Cyclic Cubic FIELD Extensions p-class TOWER GROUP Relation Rank Metabelianization Coclass Graphs
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具有宽范围负载能力双向E^(#)型WPT系统研究 被引量:2
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作者 张信 杨奕 +2 位作者 包诗媛 张路 陈诗雨 《中国电机工程学报》 北大核心 2025年第4期1610-1622,I0032,共14页
传统双向E型无线电能传输(wireless power transfer,WPT)拓扑易进入硬开关状态,导致电能传输效率低。针对此,该文提出无线电能传输系统的改进E^(#)型拓扑及其移相控制策略。首先,构建软开关状态负载范围更宽的双向E^(#)型WPT电路拓扑数... 传统双向E型无线电能传输(wireless power transfer,WPT)拓扑易进入硬开关状态,导致电能传输效率低。针对此,该文提出无线电能传输系统的改进E^(#)型拓扑及其移相控制策略。首先,构建软开关状态负载范围更宽的双向E^(#)型WPT电路拓扑数学模型,分析并提取电路实现软开关工作状态的关键变量与约束条件,理论上证明所提拓扑的有效性。然后,推导电路中线圈互感和负载阻抗等参数的解析关系式,并基于此提出可保证系统在负载时始终处于最佳工作状态的移相控制策略。该策略通过控制开关管的门极驱动信号相位,使谐振元件内部储存的能量提前或者滞后释放,从而将开关管修正回软开关状态。最后,通过仿真和实验验证所提双向E^(#)型WPT系统的有效性。实验结果表明,所提方法可保证在5~30Ω的负载范围内电路工作在软开关状态,该范围内的电能传输效率峰值达84.3%。 展开更多
关键词 双向无线电能传输 E^(#)型电路拓扑 零电压开关 移相控制
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地域类型视角下中国绅士化研究:特征、经验与展望 被引量:1
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作者 张清源 《人文地理》 北大核心 2025年第4期24-35,共12页
绅士化已成为全球城乡发展的重要理论与现实问题。伴随中国的城市更新、城市蔓延和乡村振兴等进程,绅士化在多类型地域空间广泛发生,催生了各异的社会空间结果。基于城乡空间结构和不平衡发展等理论,文章构建了中国绅士化经验研究的分... 绅士化已成为全球城乡发展的重要理论与现实问题。伴随中国的城市更新、城市蔓延和乡村振兴等进程,绅士化在多类型地域空间广泛发生,催生了各异的社会空间结果。基于城乡空间结构和不平衡发展等理论,文章构建了中国绅士化经验研究的分析框架。通过统计分析和地理可视化,系统梳理了中国绅士化的经验研究文献。研究发现:城市群是中国绅士化研究的热点区,都市边缘区和腹地等日益受到重视;绝大多数研究者对绅士化持批判或相对中立的价值立场。绅士化在多类型地域呈现差异性:城市内城多表现为单位住宅、老旧街道的商业绅士化、教育绅士化等形式;都市边缘区多表现为大规模新城建设下的新建绅士化、绿色绅士化;腹地小城镇和乡村则多表现为乡村绅士化和旅游绅士化。多类型地域的绅士化在发生路径和内在逻辑上紧密关联,反映了中国城乡关系的复杂变迁。未来研究可以从都市边缘区的大规模绅士化、绅士化过程的人口流向、社区的整体演变史及制度特征等方面进行深化。 展开更多
关键词 绅士化 地域类型 经验研究 社会正义 中产阶层
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基于结构方程模型的老年2型糖尿病患者医院-家庭过渡期用药依从性的影响路径 被引量:1
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作者 方倩 李德琴 +3 位作者 詹静 赵萍 吕佳 王佳薇 《中国药物与临床》 2025年第12期778-782,共5页
目的基于结构方程模型(SEM)探讨老年2型糖尿病患者医院-家庭过渡期用药依从性的影响路径,改善患者用药依从性。方法使用便利抽样法选取2022年6月至2024年9月中国人民解放军联勤保障部队第九〇三医院内分泌科收治的287例老年2型糖尿病患... 目的基于结构方程模型(SEM)探讨老年2型糖尿病患者医院-家庭过渡期用药依从性的影响路径,改善患者用药依从性。方法使用便利抽样法选取2022年6月至2024年9月中国人民解放军联勤保障部队第九〇三医院内分泌科收治的287例老年2型糖尿病患者作为研究对象,使用一般资料调查表、8项Morisky药物依从性量表(MMAS-8)、社会支持评定量表(SSRS)进行调查,采用SEM探讨患者医院-家庭过渡期用药依从性的影响路径。结果老年2型糖尿病患者的MMAS-8得分为(5.7±1.0)分,SSRS总分为(37±3)分。老年2型糖尿病患者的已婚、高学历与其社会支持呈正相关(P均<0.05),同时已婚、高学历、社会支持均与其用药依从性呈正相关(P<0.05)。SEM显示,已婚及高学历患者的社会支持及用药依从性均更高(均P<0.05),社会支持正向患者影响用药依从性(P<0.05)。结论老年2型糖尿病患者医院-家庭过渡期用药依从性与其婚姻情况、学历及社会支持相关,护理人员或能通过提供更多情感支持、健康教育和实际帮助以提升患者用药依从性。 展开更多
关键词 潜在类别分析 糖尿病 2型 老年人 医院-家庭过渡期用药依从性 影响路径
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异地城镇化背景下农民工家庭代际关系类型与影响因素
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作者 崔烨 靳小怡 胡钊源 《人口与发展》 北大核心 2025年第3期81-90,共10页
利用深圳市农民工调查数据,基于代际团结理论、纳入冲突维度,采用潜在类别模型构建农民工代际关系类型;基于构建的“宏观结构-微观资源”解释框架,使用分层Logistic模型分析这些关系类型的影响因素。研究发现,农民工家庭存在远但和谐型... 利用深圳市农民工调查数据,基于代际团结理论、纳入冲突维度,采用潜在类别模型构建农民工代际关系类型;基于构建的“宏观结构-微观资源”解释框架,使用分层Logistic模型分析这些关系类型的影响因素。研究发现,农民工家庭存在远但和谐型、近但有间型、远但亲近型、远且不和谐型等关系类型,继最传统的远但和谐型、最现代的远且不和谐型成为次普遍的关系类型,反映了异地城镇化的深刻影响。跨区域流动、养老机构印象差与远但和谐型关系负相关,反映了异地城镇化对农民工家庭即时、深远的冲击。长期和短期资源交换总体上有助于维系传统代际关系,表明利他动机和互惠原则对异地城镇化风险的应对。研究结论可为促进农民工和谐代际关系和家庭福利提供政策启示。 展开更多
关键词 异地城镇化 农民工 代际关系类型 潜在类别分析
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基于图注意力网络(GAT)的单细胞类型注释方法研究
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作者 孙熠伟 徐淑坦 《基因组学与应用生物学》 北大核心 2025年第6期561-577,共17页
单细胞转录组测序(single-cell RNA sequencing,scRNA-seq)在揭示细胞异质性方面具有重要意义,但现有细胞类型注释方法存在着跨物种适应性、泛化性、类别不平衡等问题。本文提出了一种基于图注意力网络(graph attention network,GAT)的... 单细胞转录组测序(single-cell RNA sequencing,scRNA-seq)在揭示细胞异质性方面具有重要意义,但现有细胞类型注释方法存在着跨物种适应性、泛化性、类别不平衡等问题。本文提出了一种基于图注意力网络(graph attention network,GAT)的细胞类型注释方法ScLabeler。该方法通过结合类别均衡优化策略和图注意力机制,增强了细胞间复杂关系的捕捉,提升了注释的精确度。实验结果表明,ScLabeler在人类(Homo sapiens)、小鼠(Mus musculus)、斑马鱼(Danio rerio)等多物种数据集上的细胞类型注释效果相比Seurat、ScGCN等方法都更为优异,注释的准确率提高了4.62%~35.76%,F1分数提高了5.21%~39.73%;另外注释的结果证明了ScLabeler在细胞类型低丰度识别方面[斑马鱼组织调整兰德指数(adjusted rand index,ARI)提高了9个百分点]与对其他物种泛化性方面[归一化互信息(normalized mutual information,NMI)提升幅度达到11.76%~123.53%]有显著提升。此外,通过UMAP和Sankey图等可视化工具,直观展示了细胞类型分布及预测一致性,为单细胞组学研究提供了高效的注释工具。ScLabeler源码可在https://github.com/bioinfolabdev/ScLabeler下载。 展开更多
关键词 图注意力网络(GAT) 单细胞转录组测序(scRNA-seq) 细胞类型注释 类别不平衡
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不同垂直骨面型的骨性Ⅲ类患者正畸掩饰性治疗前后的软硬组织及审美评价差异
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作者 苏晓平 林小青 +2 位作者 郑雅茹 张彦君 吕晓君 《中国美容医学》 2025年第10期157-162,共6页
目的:探讨不同垂直骨面型的骨性Ⅲ类患者正畸掩饰性治疗前后的软硬组织变化状况及审美评价差异。方法:回顾性分析2018年7月-2023年8月在笔者医院进行治疗的90例骨性Ⅲ类错(牙合)畸形患者的临床资料,依据垂直骨面型不同分成高角组(n=28)... 目的:探讨不同垂直骨面型的骨性Ⅲ类患者正畸掩饰性治疗前后的软硬组织变化状况及审美评价差异。方法:回顾性分析2018年7月-2023年8月在笔者医院进行治疗的90例骨性Ⅲ类错(牙合)畸形患者的临床资料,依据垂直骨面型不同分成高角组(n=28)、均角组(n=32)及低角组(n=30),所有患者均开展正畸掩饰性治疗。分析三组患者治疗前后软硬组织及美观评价变化情况。结果:治疗前,三组Z角、颏前部软组织厚度(Pog-Pog’)、颏顶部软组织厚度(Gn-Gn’s)、FMIA角及下切牙到鼻根点-下齿槽座点连线的垂直距离(Ll-NB)比较差异均有统计学意义(P<0.05)。治疗后,高角组Z角、FMIA角、Pog-Pog’、U1-NA、L1-NB及U1-NA距与治疗前比较差异有统计学意义(P<0.05),均角组Z角、Wits、U1-NA、L1-NB、U1-NA距及L1-NB距与治疗前比较差异有统计学意义(P<0.05);低角组Z角、Wits、U1-NA、L1-NB、U1-NA距及L1-NB距与治疗前比较差异有统计学意义(P<0.05)。三组Z角、FMIA、Pog-Pog’、Gn-Gn’治疗前后变化差值比较差异均有统计学意义(P<0.05),三组Wits、U1-NA、U1-NA距及L1-NB距、L1-NB治疗前后变化差值比较差异无统计学意义(P>0.05)。治疗后,三组普通人与正畸医师美观评分均上升,且三组美观评分比较差异无统计学意义(P>0.05)。结论:不同垂直骨面型的骨性Ⅲ类错(牙合)畸形患者正畸掩饰性治疗后均可有效改善美观性,但正畸掩饰性治疗仅能适当改善骨性不协调,无法彻底改变骨面型。 展开更多
关键词 垂直骨面型 骨性Ⅲ类错(牙合)畸形 掩饰性治疗 审美评价
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教育、科技、人才一体发展与高水平研究型大学建设 被引量:3
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作者 李立国 《国家教育行政学院学报》 北大核心 2025年第4期3-11,共9页
高水平研究型大学是教育、科技、人才的集中交汇点,是科技是第一生产力、人才是第一资源、创新是第一动力的重要连接点,在教育强国、科技强国、人才强国建设中具有独特而重要的地位与作用。建设高水平研究型大学,需要立足中国国情,遵循... 高水平研究型大学是教育、科技、人才的集中交汇点,是科技是第一生产力、人才是第一资源、创新是第一动力的重要连接点,在教育强国、科技强国、人才强国建设中具有独特而重要的地位与作用。建设高水平研究型大学,需要立足中国国情,遵循教育规律,将高水平研究型大学建设成为研究生教育特别是博士研究生教育中心、基础研究主力军和重大科技突破策源地,建立科技创新与人才培养相互支撑的有效机制。优化“双一流”建设高校的学科结构与区域布局,加快新型研究型大学建设,使部分“双一流”建设高校和部分新型研究型大学早日成为高水平研究型大学。 展开更多
关键词 教育、科技、人才一体发展 高水平研究型大学 博士生教育 科技创新 “双一流”建设高校 新型研究型大学
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面向MTC的新型多信道ALOHA随机接入方案
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作者 韩会梅 王康琪 卢为党 《高技术通讯》 北大核心 2025年第4期385-392,共8页
针对机器类通信(machine type communication,MTC)中海量用户接入网络造成的低成功接入概率问题,本文提出了一种面向MTC的新型多信道ALOHA(additive links on-line Hawaii area)随机接入方案。该方案分为导频传输阶段和数据传输阶段:导... 针对机器类通信(machine type communication,MTC)中海量用户接入网络造成的低成功接入概率问题,本文提出了一种面向MTC的新型多信道ALOHA(additive links on-line Hawaii area)随机接入方案。该方案分为导频传输阶段和数据传输阶段:导频传输阶段允许一个信道被多个用户使用,而数据传输阶段根据用户的不同接入时延需求采用不同的数据传输策略,并且采用接入等级限制对数据传输的用户进行拥塞控制,进而提升用户成功接入概率。仿真结果表明,与现有多信道ALOHA随机接入方案相比,该方案能够极大地提升时延敏感用户成功接入概率和总用户成功接入概率。 展开更多
关键词 机器类通信 多信道ALOHA 随机接入 接入等级限制
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